Had this problem for weeks. (2020 13" M1 MacBook Pro)
What finally worked:
turn off macbook
hold power - keep holding - boot options (safe mode) - select options
"Reinstall" Big Sur
Installed 11.2.1 over existing Big Sur install (keeping Users intact, i.e. not a clean install)
DennisO
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution